Closure cap and package



Feb. 10; 1942. w. P. WHITE CLOSURE CAP AND PACKAGE Filed April 26, 1937n u n u Patented Feb. 10, 1942 Pres CLOSURE CAP AND PACKAGE William P.White, Glencoe, ]ll., asslgnor to White Cap Company, Chicago, 111., acorporation of Delaware Claims.

This invention relates to closure caps of the sort utilized for sealingjars, tumblers or the like for packaging and preservation of ioodstufisand similar commodities. It relates particularly to that type of closurecap wherein a hermetic seal is formed upon the packing vessel by aplastic gasket which is compressed between the top of the shell of thecap and the mouth rim of the vessel, the closure being held in place onthe vessel by atmospheric pressure consequent upon the exhaustion orremoval of air from the unoccupied head space of the vessel.

An object of the invention is the provision of such a closure cap whichmay be manufactured at low cost, and which is particularly adapted toform a very secure connection with the packing vessel on which it issealed, and which, furthermore, is of a character such as to facilitateits removal from the vessel without preliminary puncturing of the shellto equalize the air pressure.

Other and further objects of the invention will be pointed out orindicated hereinafter, or will be apparent upon an understanding of itscharacter or employment of it in actual use.

For the purpose of aiding in an explanation of the invention, I show inthe accompanying drawing forming a part of this specification, andhereinafter describe, one form of closure cap constituting an embodimentof it. It is to be understood, however, that this is presented simplyfor the purpose of illustration, and hence is not to be construed in anyfashion calculated to limit the appended claims short of the true andmost comprehensive scope of the invention in the art.

In said drawing, Fig. 1 is a bottom view of a closure cap embodying theinvention;

lationship of the parts after the closure has been pressed down tosealing position on the receptacle;

Fig. 5 is a similar illustration in the nature of'a section on line 5-5of Fig. l and serving to illustrate the relationship of the parts afterthe closure has been pressed down to scaling position on the receptacle;and

Fig. 6 is a sectional elevation showing the closure in sealing positionon a suitable receptacle.

There are various kinds of closure caps, employing metal shells andsealing gaskets of various types, which are intended to be applied topacking vessels after exhaustion of air therefrom and to be held on thepacking vessel by the external atmospheric pressure. I

' In order to remove such closures from the receptacles on which theyare thus sealed, it is necessary in most instances, to puncture theclosure, or otherwise mutilate or distort it, in order to admit air forthe purpose of equalizing the internal pressure with the externalatmospheric pressure. Such puncturing or distortion of the closure, as arule, renders it unfit for further use as an efiective closure for thereceptacle.

The present invention is designed to obviate the necessity of puncturingthe closure and to avoid permanent distortion of it in the operation ofadmitting air to the sealed package for the purpose of permittingremoval of the closure.

The present invention also is designed to increase the adhesive orretentive cooperation of the sealing gasket with the receptacle, and toattain various other advantages which will be pointed out as thedescription proceeds.-

An understanding of the nature of the present invention may be had mostquickly by consideration of the illustrative embodiment shown in thedrawing which will now be described.

The closure cap here shown comprises a. shell,

' which may bemade of sheet metal or other appropriate material, whichshell is formed with a top portion In and a depending annular skirt ii,and a sealing gasket 5 2, which is of ring type and is composed of aplastic sealing material, such as unvulcanized rubber.

As illustrated in Fig. 6, the shell is formed in such proportions thatthe lower margin of the skirt H is of materially greater diameter thanthe mouth portion of the receptacle V for which the closure is intended.As a consequence,- the lower margin of the skirt, when the closure is inplace on the receptacle, will be spaced 9. substantial distanceoutwardly from the periphery of the receptacle. The lower margin of theskirt is stiffened and reinforced by being spun upwardly and outwardlyto form a continuous circumferential bead it.

The upper portion of the skirt which is immediately adjacent the top illis formed as a restricted portion Ila, on an internal diameter which issubstantially less than that of the lower portion of the skirt and butslightly greater than the external diameter of the mouth of thecontainer, and below the portion Ila, the skirt is fluted in suchfashion that its inner face presents a plurality of inwardly projectingembossments llb which have portions of their inner faces extendingdownwardly as extensions of the portion I la, said embossments llb beinginterspaced by recesses He, the inner surfaces of which are uponapproximately the same radius as the lower portion of the skirt ll.Spacing between the embossments ll b may be such as desired.

The pre-formed ring gasket l2, which is of general rectangular crosssection, is of such diameter as to fit within the small-diameter portionlla of the skirt, and the thickness of the gasket is such that when itsupper surface is in contact with the top It], its lower surface will besomewhat below the cylindrical portion of the small-diameter skirtportion Ila. The gasket is adherently attached to the shell top Ill.

The closure cap is sealed on the receptacle by pressing it downwardlythereon after air has been exhausted or displaced from.within the capand receptacle. Fig. 3 serves to illustrate the relationship of thevarious portions of the cap to the mouth portion of the receptacle whenthe cap is first placed thereon, it being noted that the gasket restsupon the mouth rim R of the receptacle. The operation of placing the capon the receptacle, which operation is usually performed by automaticmachinery, is facilitated by the relatively large diameter of the lowerportion of the shell skirt, which permits the mouth of the vessel toenter freely, even though the cap may not be in accurate concentricrelationship with the receptacle. The inwardly extending embossmentsllb, which have their innermost portions disposed on a circumferencecorresponding to that of the gasket and slightly larger than that of thereceptacles mouth, act as guides to center the cap on the receptacle,thus causing the gasket to come to rest on the mouth rim, as

illustrated in Fig. 3, entirely around the mouth, thus effecting acontinuous sealing contact between the gasket and mouth rim. Downwardpressure is then applied to the top of the cap to force it downwardly onthe receptacle, which causes the mouth rim of the receptacle to beforced into the plastic gasket. In this operation, the small-diameterportion lla of the cap skirt retains the upper portion of the gasketagainst spreading. As a consequence, a greater proportion of the gasketmaterial which is displaced by the intrusion of the receptacles mouth isdisplaced downwardly than would be the case if the upper portion of thegasketwere free to move outwardly. At the points where the embossmentsIII) are in contact with or quite close to the peripheral surface of thereceptacle, there can be relatively little downward displacement of the.gasket material. However, in the intervening spaces, the gasket materialmay be plastically displaced to a considerable extent downwardly alongthe peripheral surface of the receptacles mouth. Of course, displacementof the gasket material likewise occurs downward along the inner surfaceof the receptacles mouth. In Fig;

5 is illustrated the relationship of the parts Where the embossment llbis closely associated with the periphery of the receptacle, and in Fig.4 is illustrated the relationship of the parts at a point between theembossments where there is a substantial space between the periphery ofthe receptacles mouth and the skirt of the cap.

In Fig. 6 the closure is shown in sealed position on the receptacle. Itwill be observed that because of the form of the shell skirt, its lowermargin is spaced a substantial distance outwardly from the peripheralsurface of the portion of the receptacle which it encompasses, theportions l lb acting as spacers and as guiding or centering elements tomaintain the closure in concentric relationship with the receptacle.This spacing of the margin of the skirt outwardly from the periphery ofthe receptacle is a desired and ad vantageous feature, for the purposeof permitting said margin to be engaged effectively by a suitableimplement by which upward pressure may be exerted upon it to force theclosure upwardly. Such an implement is indicated at K. To facilitate theapplication of upward pressure to the closure, the receptacle preferablyis provided with an outwardly extending ledge or shoulder L, located ata proper distance below its mouth, upon which the implement may befulcrumed to exert leverage upwardly against the reinforcing bead l4. Bysuch operation the closure may be pried upwardly sufiiciently to breakthe seal and permit air to enter the package, whereupon the closure maybe lifted oil easily.

The marginal bead l4 reinforces the shell skirt against distortion bythe pressure applied to it in this operation. and the embossments llbalso act as stiffening elements in the skirt. Naturally,

as the closure is pried upwardly at one side, it is tilted toward theother side, and the fact that the margin of the skirt is spaced awayfrom the receptacle at said opposite side permits the clo-- sure to tiltwithout opposition or inerference between those portions at that point.All of these features cooperate to prevent distortion of the shell andthus enable it to withstand the pressure necessary to tilt itsufficiently to break the seal. Thus preliminary puncturing of the shellis rendered unnecessary, and it may be removed in such condition as tobe continued in use as an effective closure for the receptacle.

I claim:

1. A closure for sealing packing receptacles. comprising a shell havinga top and depending annular skirt, said skirt being formed at its upperend with a shallow restricted annular portion which is of relativelysmall diameter, and with a substantially non-distensible lower portionwhich at both its upper and lower-limits is of materially largerinternal diameter than said restricted portion, said skirt having formedin its lower portion a plurality of circumferentially distributedinwardly projecting substantially rigid embossments which merge at theirupper ends into said restricted portion and at their lower ends intosaid lower portion at a distance above its lower margin and outwardlybeyond said restricted portion, and a gasket of plastic sealing materialsecured in the shell against the top with its periphery alongside saidrestricted portion of the skirt, -said embossments in the skirt beingdisposed on a radius from its axis such as to permit the mouth of theintended vessel to enter freely into sealing contact with the gasketwithout any distortion of the shell, and serving to space the lowerportion of the skirt outwardly from the mouth of the vessel.

2. A closure as specified in claim 1 and wherein said embossments areformed as downward continuations of said restricted portion and withtheir innermost parts on substantially the same radius as the innersurface thereof.

3. A closure as specified in claim 1 and wherein the innermost portionsof said embossments extend downwardly from the periphery of the gasket.

4. In a package having a receptacle with a mouth rim and an outwardlyprojecting peripheral ledge therebelow, a closure comprising a shellformed with a top and a depending annular skirt 10 side the periphery ofthe gasket, said shell being provided with substantially rigid inwardlyprojecting embossments spaced from one another circumferentially andextending downwardly from said restricted portion and terminating shortof the lower margin of the skirt, said embossments being spaced from theaxis of the shell sufiiciently to accommodate the, mouth rim of thereceptacle freely but cooperating with its periphery to maintain theshell in -coaxial relationship thereto and with the lower portion of theskirt spaced from the periphery of the mouth rim above the peripheralledge.

5. In a package, a construction as specified in claim 1 and wherein thelower marginal'portion of the shell skirt is formed with an annularstif-

